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.TH curl_easy_duphandle 3 "19 Sep 2014" "libcurl" "libcurl"
.SH NAME
curl_easy_duphandle - Clone a libcurl session handle
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURL *curl_easy_duphandle(CURL *handle);
.fi
.SH DESCRIPTION
This function returns a new curl handle, a duplicate, using all the options
previously set in the input curl \fIhandle\fP. Both handles can subsequently
be used independently and they must both be freed with
\fIcurl_easy_cleanup(3)\fP.

Any options that the input handle has been told to point to (as opposed to
copy) with previous calls to \fIcurl_easy_setopt(3)\fP, are pointed to by the
new handle as well. You must therefore make sure to keep the data around until
both handles have been cleaned up.

The new handle does \fBnot\fP inherit any state information, no connections,
no SSL sessions and no cookies. It also does not inherit any share object
states or options (created as if \fICURLOPT_SHARE(3)\fP was set to NULL).

If the source handle has HSTS or alt-svc enabled, the duplicate gets data read
data from the main file name to populate the cache.

In multi-threaded programs, this function must be called in a synchronous way,
the input handle may not be in use when cloned.
.SH EXAMPLE
.nf
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    CURL *nother;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
    nother = curl_easy_duphandle(curl);
    res = curl_easy_perform(nother);
    curl_easy_cleanup(nother);
    curl_easy_cleanup(curl);
  }
}
.fi
.SH AVAILABILITY
Added in 7.9
.SH RETURN VALUE
If this function returns NULL, something went wrong and no valid handle was
returned.
.SH SEE ALSO
.BR curl_easy_cleanup (3),
.BR curl_easy_init (3),
.BR curl_easy_reset (3),
.BR curl_global_init (3)
